1. Field of the Invention
The present invention relates to a cellular phone, more particularly to improvement in a cellular phone with respect to which an operation key can be attached/detached.
2. Description of the Related Art
The technology of cellular phones relating to enlarged display parts, such as U.S. Pat. No. 5,048,077 (REFLECTION TWCH) and U.S. Pat. No. 5,970,418 (INTERNATIONAL BUSINESS MACHINES), is known.
Moreover, techniques of attaching/detaching operation keys of the cellular phones are described, for example, in Jpn. Pat. Appln. KOKAI Publication Nos. 06-276265 and 09-321848. These publications disclose a constitution of the attaching/detaching of the operation key, and a display section is disposed in an attaching/detaching section. However, the enlarged display section does not exist in a phone main body, and a cooperative function with the operation key for using an enlarged display or the constitution of the enlarged display is not considered.
In recent years, the cellular phones have been used not only for phone calls but also as information data obtaining means, such as an internet homepage browser. For the display, portable information apparatuses such as a personal digital assistant (PDA) are connected to the cellular phones and used. In this case, the cellular phone is also used as a communication modem.
On the other hand, the cellular phones in which enlarged display section are incorporated have also been developed. However, when an operator holds an apparatus and looks at the enlarged display section in performing a character input operation or an instruction operation of a browser for inspection in a keyboard, there is a disadvantage that key buttons cannot be seen in a position of the keyboard disposed in a conventional cellular phone main body. Furthermore, positions of fingers for operating the key buttons cannot meet appropriate positions, thus there is a disadvantage that the phone is difficult to operate.
In consideration of the above-described respects, as a desired use style, it has been proposed that the cellular phone should be held in one hand and a remote controller should be held in the other hand while looking at the enlarged display so as to give operation instructions such as key input.
Moreover, in order to realize the cellular phone capable of being actually felt to include a screen which has a large display easy to see, a constituting size of an optical system for the enlarged display easily tends to be large. In addition, for the position of the enlarged display part, in a conventional usage style, considering a conventional design of a speaker section in the vicinity of an apparatus main body upper section, which is brought onto an ear, such a style that a display part is disposed around the operation key and can be browsed is desirable.
Furthermore, with the usage for making phone calls and the usage for browsing information, the usage style of the cellular phone differs. A compact integral type of style in which mobility is considered is desirable for carrying the apparatus.
Therefore, an object of the present invention is to provide a cellular phone in which an operation key for performing an input operation is not difficult to see, operation instructions can be given, a style at a usage time of the phone is not largely changed, and an apparatus is prevented from being enlarged.